Do you often start a REALLY cold motor (you are in Illinios)? Cold as in below say 35-40?

If so I would be very leary of 20w50. Your oil pressure numbers look like they will support 10w30 just fine. Try it.

An interesting test: pour some oil into a jar, put in freezer overnight. Then see how they pour.
I was amazed, years ago, at how thick Castrol GTX 20w50 was!